Haryey yvorrall



(No Model.)

H. WORRALL.

HARMONIG DAMPER FOR PIANOS.

No. 398,924. Patented Mar. 5,, 1889.

S Z w) n r I a: d A 76 N. PETERS. Plmlo-Lvthugmphcr, Washingwn, o. c.

UNITED STATES PATENT Orrin-no HARVEY "\TORRALL, O l TOPEKA, KANSAS.

HAPMONIC DAMPER FOR PIANOS.

SPECIFICATION forming part of Letters Patent No. 398,924, dated March 5, 1889. Application filed June 1 i886, Serial No. 205,130. Lilo inodeld To aZZ whom it may concern:

Be it known that I, Hanvnv WURRALL, a citizen of the United States, residing at the city of Topeka, in the county of Shawnee and State of Kansas, have invented a new and use ful Improvement in the Arrangement and Operation of the Strings in a Piano, of which the following is a specification.

The object of my. invention is to produce 1 The advantages of the invention appeai most prominently in the case of those tones which are now produced from the short strings, since all of these tones may with my invenover the string at the point where the har nating in a buffer, a.

monic node is desired. At the other end ot this lever Z is the depending finger d, termi- This buffer is struck by the spring-strip s, secured to the end of the lever and fitted with a thumb-screw, 7,

for adjusting its distance, as required, l'rom the buffer-button beneath it upon the lever purity and quality im- L. The coiled spring 0 is designed for drawing its end of the lever Z down when the ham mer 7L drops from the string 11:, so as to lift the node-producing stop S from the string.

The lever Z and its lingers d and P, with the node-producing stop and buffer as well as the springs c and .9, are constructed of any desired material. The stop S and buffer .r

, are faced, too, with any desired material, as

is the buffer-button on the lever L beneath f the springs. The relative lengths of the arms I of the lever Z and the fingers d and c are dei l i i termined by the relative position of the strin and hammer and of the position desired ior the harmonic node; so, too, the length and tion be produced from strings of any desired length equaling or exceeding even the length ot the lowest bass tone.

Figure 1 represents the device in combination with the string and its key and hammer I and complementary levers when the string is silent and the mechanism at rest.

just as the hammer is striking the string. Fig. 3 represents the harmonic vibrations produced by my invention, and Fig. t represents strength of the springs c and s.

\Vith myinvention embodied and combined with the hammer and key of a piano-string and their complementary levers, when the hammer h is thrown up by the pressure oi the linger upon the key a, the spring 3 will operate the lever I so as to bring the node-produc- Fig. 2 represents the same mechanism in its position the position of the mechanism just after the hammer has struck the string and before the i linger has left the key. All of the views present a side elevation of the mechanism.

Similar letters indicate similar parts in the several figures.

a is the key, 7i the hammer, and l. T. the complementary levers as ordinarily constructed. an is the string, and b the sounding-board. My device is seen in the lever Z, supported and operated upon the fulcrum p, which rests upon a strip firmly sustained and extending along underneath the strings. At one end is ing stop down upon the st ring just before it is struck by the hammer, and will hold it down upon the string until alter the vibrating blow is struck by the hammer, the hammer striking the string at any desired point of either of the harmonic sections created by this stop The length oi. time which ihe stop S shall bear down upon the string is determined by the adjustment oi the thumbserew 1.

\Yiili my invention constructed and operated as now described and illustrated the string may be of any desired length, providing it be an exact multiple of the harmonic section created by the node-producing stop. The string may therefore be made to provide two or any greater number of similar harmonic sections or aliquot parts, the resolution an elevated finger, e, which terminates in a bend, to which is secured the node-producing stop or harmonic damper S, suspended just of whose several vibrations shall give the principal tone desired from the string. Similarly other resultant principal tones maybe elicited from the same string by locating at proper places along the string other node-producing stops operated by pedals or by additional banks of keys.

hat I claim, and desire to secure by Letters Patent as my invention, is

l. The combination, with the hammer or key of a piano, of a node-producing stop acting in connection With the key or hammer and so arranged that by the action of the key or hammer the stop will press upon the pianostring when the string receives the blow from the hammer, thus causing the string to give out one of its harmonic tones, and be removed from contact with the string shortly after the blow from the hammer has been delivered, substantially as and for the purpose hereinbefore described.

2. The combination of the lever Z, with its fingers d and e, node-producing stop S, buffer 50, springs c and s, thumb-screw t, and bufierbutton, with the piano-strin g w and its hammer h, key a, and complementary levers L L, substantially as and for the purpose hereinbefore described.

HARVEY WORRALL.

Vitnesses:

S B. BRETT, C. L. ROGERS. 

